CINCINNATI, Dec. 14 -- In an earlier era, maybe Mike Sellers would have been an offensive lineman rather than a fullback because he is every bit of 6 feet 3, 280 pounds, complete with the ability to move people out of the way so that others might go untouched. Most of his best work is done without the ball in his hands, and he is just fine with that.

But with the Washington Redskins' season at another critical juncture Sunday afternoon at Paul Brown Stadium, Sellers found himself with the ball not once, but twice. This time, he could not open a hole for anyone, least of all himself. Instead, he gave the ball to the Cincinnati Bengals, fumbling at the goal line and turning a game-tying touchdown into a turnover, completely altering the course of what became a devastating 20-13 loss to the Bengals.

"I'm just so speechless," Sellers said.

Yet he tried to explain. The Redskins' first possession of the third quarter began with promise. They trailed 17-10, and moved efficiently from their 12-yard line deep into Cincinnati territory. A carry by running back Clinton Portis put Washington in a first-and-goal situation at the 7.

From there, Portis got one carry, down to the 3. He got another carry, and couldn't squeeze in. But Cincinnati defensive tackle Jason Shirley was called for holding on the play. The situation was perfectly set up: First and goal from just outside the 1.

"I thought we were going to surge into the end zone," Coach Jim Zorn said.

First, Zorn went away from a surge, asking quarterback Jason Campbell to roll right, where he was pressured. He looked for rookie tight end Fred Davis, but threw the ball away. Second down.

Here's where Sellers, who had just four carries this season before Sunday, came in. In a nine-year NFL career, he has just three rushing touchdowns. Even despite that fact -- and even with Portis, the NFL's third-leading rusher, in the game -- Zorn turned to his fullback. Portis, who questioned how Zorn used him in last week's loss to Baltimore, did nothing of the sort Sunday. Asked if he was upset he didn't get the ball near the goal line, Portis said: "I'm not. They made the call, and everybody had the confidence in Mike to get in."

And for a moment, that's what appeared to have happened. On second down, Sellers took the handoff from Campbell and thrust himself up the middle. Cincinnati linebacker Corey Mays delivered a jarring blow, but Sellers wriggled around in the scrum. Eventually, an official shot his arms in the air. Touchdown, it seemed. Tie game, it seemed.

"I was laying on top of somebody, I don't know who it was," Sellers said. "And I thought my second effort got me across."

But from the press box, Cincinnati assistant coaches watched replays and urged Coach Marvin Lewis to challenge the ruling. He did, and the play was overturned. Instead of a tie game, it was third down. Again, the Redskins went with both Sellers and Portis in the backfield. Zorn went through his options. "I called for Sellers early," he said, "and they stopped us a little bit. And we said, 'Let's do this again,' and just ram it right down there. I thought that was a great call."

It was not, however, a great result. This time, needing only a foot or so to score, Sellers leapt into the line of scrimmage. He was met by Cincinnati linebacker Brandon Johnson, who stopped his forward momentum. But Sellers kept churning. He held the ball with both hands and extended his arms.

"I thought I was closer than I was to the goal line," Sellers said. And as he tried to put the ball across the plane, Mays swooped in and simply took it from him. The officials' decision was instantaneous: Fumble, touchback, Cincinnati ball on the 20, disgust and dismay on the Washington sideline.

"That's the danger of doing that. You talk to your backs all the time about that," Lewis said. "When you extend the football like that and you're still moving forward, as he was, you risk losing the football."

This time, it was Zorn who challenged the ruling, throwing his red flag some 20 yards. It didn't work. The ruling did not change. But the game did.

"I think that play right there, that little drive that kept us from going in and tying the ballgame up," Zorn said, "created a major flip."

Afterward, Sellers found it hard to reflect on the turn of events. He was asked if he would have done anything differently. "I'm going to give it my all to get in the end zone, if that's what you mean," Sellers said. "But I'm just a piece of the puzzle. There's other parts to it. It's not. . . . " He trailed off. "We'll just leave it like that."